Why so big of a difference in cross section by different sources?

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Discussion Overview

The discussion revolves around the discrepancies in cross-section values for the thermal neutron capture reaction 9Be(n, r)10Be as reported by different sources. Participants explore the reasons behind the significant differences in reported values, particularly focusing on the outlier from TENDL-2011 compared to other databases.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant notes that various sources report differing cross-section values for the same reaction, highlighting a significant discrepancy with TENDL-2011's value being almost 1000 times larger than others.
  • Another participant speculates that TENDL-2011 might be using a different unit for measurement.
  • A later reply mentions that TENDL-2011 has been replaced by TENDL-2015, which aligns with other experimental data, suggesting that TENDL-2011 may have contained errors.
  • Another participant expresses surprise that TENDL-2011 provided several anomalous results compared to other sources, indicating potential issues with the data quality.

Areas of Agreement / Disagreement

Participants do not reach a consensus on which value should be trusted, and there remains uncertainty regarding the reliability of TENDL-2011's data.

Contextual Notes

There are indications that TENDL-2011 may have had errors, but the specific reasons for the discrepancies and the implications for design decisions remain unresolved.

kiwaho
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if you look up the cross section in Janis books, usually for same reaction, different cross sections are quoted by different laboratories.
For example, the values of thermal neutron capture reaction 9Be(n, r)10Be:
EAF-2010, 0.0075b
ENDF/B-VII.1, 0.01b
JEFF-3.1.2, 0.0088b
JENDL-4.0, 0.0085b
TENDL-2011, 8.17b
Obviously, the first 4 sources quote very similar values, but the the last source TENDL-2011 quotes a so different value, it is almost 1000 times than previous 4 sources.
How this happen? Which value should be trusted when design?
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My guess TENDL-2011 is using different unit.
 
I checked the online version of Janis books, see http://www.oecd-nea.org/janisweb/book/neutrons/Be9/MT102/renderer/263 . There TENDL-2011 has been replaced with TENDL-2015. The new experimental data is in agreement with the other experiments. So, probably the data "TENDL-2011" contained some error.
 
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there were more than 1 cases where TENDL-2011 gave very weird results compared to others (even some numbers seemed to be buggy)... I am amazed that people actually recorded them...
 

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